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The review presents a short background of the investigated techniques carried out on TiO2-based epoxy nanocomposites. TiO2 is one of the best nanofillers for polymers due to its aspect ratio and high intercalation chemistry. The addition of reinforcement to the matrix material generally enhances their physical properties through the interaction of the surface area of reinforcement with the matrix. The nanosize reinforcements are used to show greater enhancement in the properties such as stiffness and toughness. TiO2-based epoxy nanocomposites are particularly important and show promising applications in every field of life ranging from ships to airplanes and spaceships, sports to traveling, diagnostic to treatment, and electronics to chemistry. This review explains many preparation processes of TiO2 nanoparticles such as sol–gel, microemulsion, precipitation, anodization, hydrothermal, vapor deposition, sonication and microwave, solvothermal, solid condition giving out (milling/mechanical alloying), mechano-chemical, laser ablation and radiofrequency thermal plasma. It also elucidates the synthesis of different types of epoxy resins, their properties, modification strategies, and potential applications of TiO2 nanocomposites.

The generation of an enormous quantity of municipal solid waste (MSW) poses a potential risk to the environment and socioeconomics, globally. The rapid increase in the generation of MSW is even exacerbating the situation on a daily basis. Appropriate treatment of the prevailing MSW and eliminating/minimizing the generation of new MSW are essential to improve the quality of the environment and socioeconomic conditions. Herein, we present an overview of numerous approaches with emphasis on their challenges and opportunities for sustainable management of MSW. Following a brief instruction, a special focus is given to the 3R approach, which has not been reviewed before from the MSW perspective. Thus, to cover this literature gap, herein, we discussed 3R approach to present its potential to minimize the generation and/or elimination of MSW. For the treatment of the existing MSW, three different approaches including biological, thermal, and hydrothermal approach along with their challenges and opportunities are thoroughly discussed with suitable examples. Various MSW breakdown processes involved and their related products are also given with schemes. Moreover, the factors affecting the composition and implementation of a comprehensive MSW management program are briefly discussed. Finally, the economic feasibility of the MSW treatment methods, sociocultural status, policy, and political aspects are also highlighted for a better tomorrow.

Epoxy-based protective coatings for outdoor and marine applications are commonly used to protect metals and alloys, and architectural elements against the environmental impact. An epoxy-co-polyamide (EP-PA) polymer is synthesized by reacting pre-polymers: epoxy and polyamide resins. TiO2 nanoparticles of different sizes are embedded into EP-PA copolymer to form composite coatings on the Teflon substrate, referred to as EP-PA/TiO2. TiO2 content is varied from 0.1 to 1.0 wt.% and the electrical, thermal, and mechanical performance of composites is analyzed. Both EP-PA polymer and EP-PA/TiO2 composite coatings are characterized by FTIR spectroscopy and electron microscopy. EP-PA/TiO2 composites exhibit a uniform distribution of individual TiO2 nanoparticles in the EP-PA matrix at low TiO2 content, while some aggregates are observed at the higher TiO2 content. The size effect of TiO2 nanoparticles is also demonstrated by clear differences in the surface topography, size distribution, extent of agglomeration, and surface roughness of the EP-PA/TiO2 composites. TiO2 nanoparticles have lower surface energy and therefore, increase the hydrophobic character of the composite coatings that is revealed by the increasing water droplet contact angle. The surface resistivity of EP-PA/TiO2 composites decreased with the increasing TiO2 content, while thermal degradation temperatures are improved by 100 K (15.7 %) compared to neat EP-PA polymer. The mechanical properties such as yield strength and Young’s modulus are also enhanced by 56.9 % and 32.7 %, respectively at 1.0 wt.% TiO2 loading, while the toughness of EP-PA/TiO2 composites is comparable to the neat polymer. The remarkable enhancement in the hydrophobic character, electrical conductivity, thermal stability, and mechanical performance of EP-PA/TiO2 composites at low TiO2 content (1.0 wt.%) is achieved by the small size, high surface area, and excellent dispersion of nanoparticles in the polymeric matrix. The simultaneous improvement in properties suggests EP-PA/TiO2 composites useful as protective coatings for a variety of applications in the harsh environment.